Just a little follow-up. I took the damaged plastic visor-shaft / ball-socket anchor, cut a snippet of copper roof flashing about two inches long and 3/8-inch wide and formed a dam around the cracked inside socket, filled the “mold” with two-part epoxy and let it cure over night. I then drilled a new visor-shaft hole through the epoxy, filed the copper dam / epoxy flat. I put 1/4-20 threads on the visor shaft end and secured the shaft with a washer / nut and locktite. Spent more than an hour on this little project, but the repair functions better than the undamaged unit on passenger side.